Sub test12()
    Dim dict As New Dictionary
    Dim arr As Variant
    
    ReDim arr(1 To 3, 1 To 2)
    'создаю массив для примера
    For i = 1 To 3
        arr(i, 1) = i
        arr(i, 2) = i * 10
    Next i
    dict.Add "A", arr
    
'функция о которой идет речь
    myval = changedict(dict)

End Sub


Function changedict(ByVal dict_ As Dictionary) As String
    var_ = dict_("A")
    var_(1, 1) = 999
    var_(2, 1) = 888
    dict_("A") = var_
    changedict = "something"
End Function

Sub SaveTableToArray()
    Dim tableArray() As Variant
    Dim wordApp As Word.Application
    Dim tbl As Word.Table
    Dim i As Long, j As Long

    Set wordApp = New Word.Application
    wordApp.Visible = False
    wordApp.Documents.Open "D:\Test\doks.doc"
    Set tbl = wordApp.ActiveDocument.Tables(2)

    ReDim tableArray(1 To tbl.Rows.Count, 1 To tbl.Columns.Count)

    For i = 1 To tbl.Rows.Count
        For j = 1 To tbl.Columns.Count
            tableArray(i, j) = tbl.Cell(i, j).Range.Text
        Next j
    Next i

    wordApp.Quit
    Set wordApp = Nothing
End Sub